gdb/tui/tui-stack.c

   1 /* TUI display locator.
   2
   3    Copyright (C) 1998-2021 Free Software Foundation, Inc.
   4
   5    Contributed by Hewlett-Packard Company.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 #include "defs.h"
  23 #include "symtab.h"
  24 #include "breakpoint.h"
  25 #include "frame.h"
  26 #include "command.h"
  27 #include "inferior.h"
  28 #include "target.h"
  29 #include "top.h"
  30 #include "gdb-demangle.h"
  31 #include "source.h"
  32 #include "tui/tui.h"
  33 #include "tui/tui-data.h"
  34 #include "tui/tui-stack.h"
  35 #include "tui/tui-wingeneral.h"
  36 #include "tui/tui-source.h"
  37 #include "tui/tui-winsource.h"
  38 #include "tui/tui-file.h"
  39 #include "tui/tui-location.h"
  40
  41 #include "gdb_curses.h"
  42
  43 #define PROC_PREFIX             "In: "
  44 #define LINE_PREFIX             "L"
  45 #define PC_PREFIX               "PC: "
  46
  47 /* Strings to display in the TUI status line.  */
  48 #define SINGLE_KEY              "(SingleKey)"
  49
  50 /* Minimum/Maximum length of some fields displayed in the TUI status
  51    line.  */
  52 #define MIN_LINE_WIDTH     4    /* Use at least 4 digits for line
  53                                    numbers.  */
  54 #define MIN_PROC_WIDTH    12
  55 #define MAX_TARGET_WIDTH  10
  56 #define MAX_PID_WIDTH     19
  57
  58 \f
  59
  60 std::string
  61 tui_locator_window::make_status_line () const
  62 {
  63   char line_buf[50];
  64   int status_size;
  65   int proc_width;
  66   const char *pid_name;
  67   int target_width;
  68   int pid_width;
  69   int line_width;
  70
  71   std::string pid_name_holder;
  72   if (inferior_ptid == null_ptid)
  73     pid_name = "No process";
  74   else
  75     {
  76       pid_name_holder = target_pid_to_str (inferior_ptid);
  77       pid_name = pid_name_holder.c_str ();
  78     }
  79
  80   target_width = strlen (target_shortname ());
  81   if (target_width > MAX_TARGET_WIDTH)
  82     target_width = MAX_TARGET_WIDTH;
  83
  84   pid_width = strlen (pid_name);
  85   if (pid_width > MAX_PID_WIDTH)
  86     pid_width = MAX_PID_WIDTH;
  87
  88   status_size = width;
  89
  90   /* Translate line number and obtain its size.  */
  91   int line_no = tui_location.line_no ();
  92   if (line_no > 0)
  93     xsnprintf (line_buf, sizeof (line_buf), "%d", line_no);
  94   else
  95     strcpy (line_buf, "??");
  96   line_width = strlen (line_buf);
  97   if (line_width < MIN_LINE_WIDTH)
  98     line_width = MIN_LINE_WIDTH;
  99
 100   /* Translate PC address.  */
 101   struct gdbarch *gdbarch = tui_location.gdbarch ();
 102   CORE_ADDR addr = tui_location.addr ();
 103   std::string pc_out (gdbarch
 104                       ? paddress (gdbarch, addr)
 105                       : "??");
 106   const char *pc_buf = pc_out.c_str ();
 107   int pc_width = pc_out.size ();
 108
 109   /* First determine the amount of proc name width we have available.
 110      The +1 are for a space separator between fields.
 111      The -1 are to take into account the \0 counted by sizeof.  */
 112   proc_width = (status_size
 113                 - (target_width + 1)
 114                 - (pid_width + 1)
 115                 - (sizeof (PROC_PREFIX) - 1 + 1)
 116                 - (sizeof (LINE_PREFIX) - 1 + line_width + 1)
 117                 - (sizeof (PC_PREFIX) - 1 + pc_width + 1)
 118                 - (tui_current_key_mode == TUI_SINGLE_KEY_MODE
 119                    ? (sizeof (SINGLE_KEY) - 1 + 1)
 120                    : 0));
 121
 122   /* If there is no room to print the function name, try by removing
 123      some fields.  */
 124   if (proc_width < MIN_PROC_WIDTH)
 125     {
 126       proc_width += target_width + 1;
 127       target_width = 0;
 128       if (proc_width < MIN_PROC_WIDTH)
 129         {
 130           proc_width += pid_width + 1;
 131           pid_width = 0;
 132           if (proc_width <= MIN_PROC_WIDTH)
 133             {
 134               proc_width += pc_width + sizeof (PC_PREFIX) - 1 + 1;
 135               pc_width = 0;
 136               if (proc_width < 0)
 137                 {
 138                   proc_width += line_width + sizeof (LINE_PREFIX) - 1 + 1;
 139                   line_width = 0;
 140                   if (proc_width < 0)
 141                     proc_width = 0;
 142                 }
 143             }
 144         }
 145     }
 146
 147   /* Now create the locator line from the string version of the
 148      elements.  */
 149   string_file string;
 150
 151   if (target_width > 0)
 152     string.printf ("%*.*s ", -target_width, target_width, target_shortname ());
 153   if (pid_width > 0)
 154     string.printf ("%*.*s ", -pid_width, pid_width, pid_name);
 155
 156   /* Show whether we are in SingleKey mode.  */
 157   if (tui_current_key_mode == TUI_SINGLE_KEY_MODE)
 158     {
 159       string.puts (SINGLE_KEY);
 160       string.puts (" ");
 161     }
 162
 163   /* Procedure/class name.  */
 164   if (proc_width > 0)
 165     {
 166       const std::string &proc_name = tui_location.proc_name ();
 167       if (proc_name.size () > proc_width)
 168         string.printf ("%s%*.*s* ", PROC_PREFIX,
 169                        1 - proc_width, proc_width - 1, proc_name.c_str ());
 170       else
 171         string.printf ("%s%*.*s ", PROC_PREFIX,
 172                        -proc_width, proc_width, proc_name.c_str ());
 173     }
 174
 175   if (line_width > 0)
 176     string.printf ("%s%*.*s ", LINE_PREFIX,
 177                    -line_width, line_width, line_buf);
 178   if (pc_width > 0)
 179     {
 180       string.puts (PC_PREFIX);
 181       string.puts (pc_buf);
 182     }
 183
 184   if (string.size () < status_size)
 185     string.puts (n_spaces (status_size - string.size ()));
 186   else if (string.size () > status_size)
 187     string.string ().erase (status_size, string.size ());
 188
 189   return std::move (string.string ());
 190 }
 191
 192 /* Get a printable name for the function at the address.  The symbol
 193    name is demangled if demangling is turned on.  Returns a pointer to
 194    a static area holding the result.  */
 195 static char*
 196 tui_get_function_from_frame (struct frame_info *fi)
 197 {
 198   static char name[256];
 199   string_file stream;
 200
 201   print_address_symbolic (get_frame_arch (fi), get_frame_pc (fi),
 202                           &stream, demangle, "");
 203
 204   /* Use simple heuristics to isolate the function name.  The symbol
 205      can be demangled and we can have function parameters.  Remove
 206      them because the status line is too short to display them.  */
 207   const char *d = stream.c_str ();
 208   if (*d == '<')
 209     d++;
 210   strncpy (name, d, sizeof (name) - 1);
 211   name[sizeof (name) - 1] = 0;
 212
 213   char *p = strchr (name, '(');
 214   if (!p)
 215     p = strchr (name, '>');
 216   if (p)
 217     *p = 0;
 218   p = strchr (name, '+');
 219   if (p)
 220     *p = 0;
 221   return name;
 222 }
 223
 224 void
 225 tui_locator_window::rerender ()
 226 {
 227   gdb_assert (handle != NULL);
 228
 229   std::string string = make_status_line ();
 230   scrollok (handle.get (), FALSE);
 231   wmove (handle.get (), 0, 0);
 232   /* We ignore the return value from wstandout and wstandend, casting them
 233      to void in order to avoid a compiler warning.  The warning itself was
 234      introduced by a patch to ncurses 5.7 dated 2009-08-29, changing these
 235      macro to expand to code that causes the compiler to generate an
 236      unused-value warning.  */
 237   (void) wstandout (handle.get ());
 238   waddstr (handle.get (), string.c_str ());
 239   wclrtoeol (handle.get ());
 240   (void) wstandend (handle.get ());
 241   refresh_window ();
 242   wmove (handle.get (), 0, 0);
 243 }
 244
 245 /* Function to print the frame information for the TUI.  The windows are
 246    refreshed only if frame information has changed since the last refresh.
 247
 248    Return true if frame information has changed (and windows
 249    subsequently refreshed), false otherwise.  */
 250
 251 bool
 252 tui_show_frame_info (struct frame_info *fi)
 253 {
 254   bool locator_changed_p;
 255
 256   if (fi != nullptr)
 257     {
 258       symtab_and_line sal = find_frame_sal (fi);
 259
 260       const char *func_name;
 261       /* find_frame_sal does not always set PC, but we want to ensure
 262          that it is available in the SAL.  */
 263       if (get_frame_pc_if_available (fi, &sal.pc))
 264         func_name = tui_get_function_from_frame (fi);
 265       else
 266         func_name = _("<unavailable>");
 267
 268       locator_changed_p
 269         = tui_location.set_location (get_frame_arch (fi), sal, func_name);
 270
 271       /* If the locator information has not changed, then frame information has
 272          not changed.  If frame information has not changed, then the windows'
 273          contents will not change.  So don't bother refreshing the windows.  */
 274       if (!locator_changed_p)
 275         return false;
 276
 277       for (struct tui_source_window_base *win_info : tui_source_windows ())
 278         {
 279           win_info->maybe_update (fi, sal);
 280           win_info->update_exec_info ();
 281         }
 282     }
 283   else
 284     {
 285       symtab_and_line sal {};
 286
 287       locator_changed_p = tui_location.set_location (NULL, sal, "");
 288
 289       if (!locator_changed_p)
 290         return false;
 291
 292       for (struct tui_source_window_base *win_info : tui_source_windows ())
 293         win_info->erase_source_content ();
 294     }
 295
 296   return true;
 297 }
 298
 299 void
 300 tui_show_locator_content ()
 301 {
 302   if (tui_is_window_visible (STATUS_WIN))
 303     TUI_STATUS_WIN->rerender ();
 304 }
 305
 306 /* Command to update the display with the current execution point.  */
 307 static void
 308 tui_update_command (const char *arg, int from_tty)
 309 {
 310   execute_command ("frame 0", from_tty);
 311 }
 312
 313 /* Function to initialize gdb commands, for tui window stack
 314    manipulation.  */
 315
 316 void _initialize_tui_stack ();
 317 void
 318 _initialize_tui_stack ()
 319 {
 320   add_com ("update", class_tui, tui_update_command,
 321            _("Update the source window and locator to "
 322              "display the current execution point.\n\
 323 Usage: update"));
 324 }